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41.
For the prevention of postoperative ocular infections prophylactic topical antibiotics are routinely used. Studies evaluating comparative difference between single dose versus multiple dose administration on aqueous humour concentration of moxifloxacin are lacking. This study compared the aqueous humour concentration of moxifloxacin following its topical administration in rabbit eyes with two dose regimens. Twelve albino rabbits were divided into two groups. In group-1, two drops were administered thrice (total six drops) at 2 min intervals, in both the eyes; in group-2, two drops of moxifloxacin were administered three times a day for three days and also two h before aqueous humour collection i.e. on fourth day. Mean aqueous humour concentrations were calculated and compared using Student''s ‘t’ test and P<0.05 was considered significant. Moxifloxacin concentration in aqueous humour in group-1 was 23.79 μg/ml and in group-2 was 42.08 μg/ml. Both dosing regimens produced substantially higher aqueous concentrations than the known minimum inhibitory concentration for most bacteria. Moxifloxacin concentration in aqueous humour with multiple instillations is significantly higher than single instillation (P<0.05), which is adequate to cover ciprofloxacin-resistant gram-negative bacteria. Repeated topical moxifloxacin administration achieved significantly higher aqueous humour concentrations than single administration.  相似文献   
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Post-partum haemorrhage (PPH) is a life-threatening obstetric complication and the leading cause of maternal death. Any bleeding that results in or could result in haemodynamic instability, if untreated, must be considered as PPH. There is no controversy about the need for prevention and treatment of PPH. The keystone of management of PPH entails first, non-invasive and nonsurgical methods and then invasive and surgical methods. However, mortality remains high. Therefore, new advancements in the treatment are most crucial. One such advancement has been the use of recombinant activated factor VII (rFVIIa) in PPH. First used 12 years back in PPH, this universal haemostatic agent has been effectively used in controlling PPH. The best available indicator of rFVIIa efficacy is the arrest of haemorrhage, which is judged by visual evidence and haemodynamic stabilization. It also reduces costs of therapy and the use of blood components in massive PPH. In cases of intractable PPH with no other obvious indications for hysterectomy, administration of rFVIIa should be considered before surgery. We share our experience in a series of cases of PPH, successfully managed using rFVIIa.  相似文献   
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Our group has previously found that in silico, mechanical anisotropy may be interrogated by exciting transversely isotropic materials with geometrically asymmetric acoustic radiation force excitations and then monitoring the associated induced displacements in the region of excitation. We now translate acoustic radiation force-based anisotropy assessment to human muscle in vivo and investigate its clinical relevance to monitoring muscle degeneration in Duchenne muscular dystrophy (DMD). Clinical anisotropy assessments were performed using Viscoelastic Response ultrasound, with a degree of anisotropy reflected by the ratios of Viscoelastic Response relative elasticity (RE) or relative viscosity (RV) measured with the asymmetric radiation force oriented parallel versus perpendicular to muscle fiber alignment. In vivo results from rectus femoris and gastrocnemius muscles of boys aged ~7.9–10.4 y indicate that RE and RV anisotropy ratios in rectus femoris muscles of boys with DMD were significantly higher than those of healthy control boys (RE: DMD?=?1.51 ± 0.87, control?=?0.99 ± 0.69, p?=?0.04, Wilcoxon rank sum test; RV: DMD?=?1.04 ± 0.71, control?=?0.74 ± 0.22, p?=?0.02). In the gastrocnemius muscle, only the RV anisotropy ratio was significantly higher in dystrophic than control patients (DMD?=?1.23 ± 0.35, control?=?0.88 ± 0.31, p?=?0.04). In the dystrophic rectus femoris muscle, the RE anisotropy ratio was inversely correlated (slope?=?–0.03/lbf, r?=?–0.43, p?=?0.07, Pearson correlation) with quantitative muscle testing functional output measures but was not correlated with quantitative muscle testing in the dystrophic gastrocnemius. These results suggest that Viscoelastic Response RE and RV measures reflect differences in mechanical anisotropy associated with functional impairment with dystrophic degeneration that are relevant to monitoring DMD clinically.  相似文献   
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Elevation of serum parathyroid hormone (PTH) level in eucalcemic patients after parathyroidectomy for primary hyperparathyroidism has been described in up to 40% of patients, but little is known about its etiology or clinical significance. To better understand the cause of this phenomenon, we studied 49 patients without renal dysfunction or osteomalacia who underwent parathyroidectomy for primary hyperparathyroidism. Patients were categorized into 2 groups based on their serum PTH and calcium levels after parathyroidectomy: (1) elevated PTH with eucalcemia (n = 21), (2) normal PTH with eucalcemia (n = 28). Elevation of serum PTH with eucalcemia after parathyroidectomy occurred in 43% of patients. Patients in group 1 had significantly higher preoperative and postoperative mean serum PTH levels and significantly lower postoperative serum levels of 1,25(OH)(2)D(3), 1,25(OH)(2)D(3)/25(OH)D(3) ratio, and 1,25(OH)(2)D(3)/PTH ratio compared with patients in group 2. Serum PTH in group 1 patients normalized as early as 3 months, but remained elevated in some patients for more than 4 years, and was not associated with development of recurrent hypercalcemia. Normalization of serum PTH in group 1 patients was associated with significant increase in 1,25(OH)(2)D(3) and 1,25(OH)(2)D(3)/PTH ratio. Our data suggest that elevation of serum PTH in eucalcemic patients after parathyroidectomy is a frequently reversible state of resistance of the kidneys to PTH-mediated 1-alpha hydroxylation of 25(OH)D(3) and does not signify subsequent recurrence of hyperparathyroidism.  相似文献   
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The burden of chronic diseases, such as heart disease, cancer, diabetes, and mental disorders is high in low-income and middle-income countries and is predicted to increase with the ageing of populations, urbanisation, and globalisation of risk factors. Furthermore, HIV/AIDS is increasingly becoming a chronic disorder. An integrated approach to the management of chronic diseases, irrespective of cause, is needed in primary health care. Management of chronic diseases is fundamentally different from acute care, relying on several features: opportunistic case finding for assessment of risk factors, detection of early disease, and identification of high risk status; a combination of pharmacological and psychosocial interventions, often in a stepped-care fashion; and long-term follow-up with regular monitoring and promotion of adherence to treatment. To meet the challenge of chronic diseases, primary health care will have to be strengthened substantially. In the many countries with shortages of primary-care doctors, non-physician clinicians will have a leading role in preventing and managing chronic diseases, and these personnel need appropriate training and continuous quality assurance mechanisms. More evidence is needed about the cost-effectiveness of prevention and treatment strategies in primary health care. Research on scaling-up should be embedded in large-scale delivery programmes for chronic diseases with a strong emphasis on assessment.  相似文献   
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Udupa  KB; Lipschitz  DA 《Blood》1982,59(6):1267-1271
The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep.  相似文献   
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